The invention relates to an anti-skid chain for vehicle tyres, with a retaining device, which, when the chain is assembled, comes to rest respectively against the inner side and the outer side of the tyre, for chain-strand lengths extending over the tread, in which chain a tensioning strand serves for tensioning the inner retaining device which can be slipped over the tyre and which has a certain natural rigidity, which tensioning strand bridges a gap between the ends of the inner retaining device and the free end of which, after being deflected at least once, is guided over the tread of the tyre to the outer retaining device.
In comparison with anti-skid chains with inner and outer retaining devices formed by side chains and collapsing into one another when dismantled, anti-skid chains of the type mentioned above offer the advantage that they are easier to assemble and that there is practically no need for occasionally complicated disentanglement of the chain network before assembly.
In a known anti-skid chain of the abovementioned type, the tensioning strand is deflected to the tread of the tyre by means of a lug connected fixedly to the end of an elastic hoop forming the inner retaining device (German Offenlegungsschrift No. 2,556,115). Practice has taught that in the case of such a chain there is no guarantee that, when the chains are tensioned, the hoop ends maintain a sufficiently long distance from the tread of the tyre. On the contrary, there is a danger that, when the chain is tensioned, the hoop end having the deflection lug will be pulled outwards away from the wheel axis, that is to say into the tread region, where it can not only be damaged itself but can also cause damage to the vehicle.
The danger indicated, which has hitherto prevented the introduction of known anti-skid chains of the type in question, cannot be eliminated even by using, according to an older proposal, instead of a deflection lug connected fixedly to the end of the inner retaining device a deflection lug suspended in a lug located at the end of a hoop-shaped retaining device. Although by replacing a deflection lug with a deflection sleeve it becomes easier to tighten the tensioning chain and, especially during assembly, the danger of chain-strand lengths becoming hooked to the rearside of the tyre is reduced, nevertheless, the use of the older anti-skid chain mentioned likewise cannot give full satisfaction.